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Neutron-diffraction study of the solid layers at the liquid-solid boundary in 4He films adsorbed on graphite
(American Physical Society, 1981)
A neutron scattering study of the structure of 4He films adsorbed on graphite is reported. Diffraction from helium monolayers at a temperature of 1.2 K shows the formation of an incommensurate, triangular-lattice solid ...
Collective Excitations in Ethane Monolayers Adsorbed on Graphite (0001) Surfaces
(American Physical Society, 1984)
Inelastic incoherent neutron spectra below 4.1 THz have been obtained for the √3×4 "herringbone" and √3×√3 "on-end" monolayer phases of ethane adsorbed on graphite basal planes. One-phonon cross sections calculated ...
Calculated effective Hamiltonian for La2CuO4 and solution in the impurity Anderson approximation
(American Physical Society, 1988)
We report local-density-functional calculations of hybridization matrix elements and effective electron-electron interactions in La2CuO4 defining a general effective Hamiltonian that we propose as an appropriate starting ...
Detection of the gravitomagnetic field using an orbiting superconducting gravity gradiometer. Theoretical principles
(American Physical Society, 1989)
The angular momentum of the Earth produces gravitomagnetic components of the Riemann curvature tensor, which are of the order of 10-10 of the Newtonian tidal terms arising from the mass of the Earth. These components could ...
Anomalous layering of Fe(CO)5 adsorbed on graphite
(American Physical Society, 1989)
Synchrotron x-ray diffraction experiments reveal the adsorption of iron pentacarbonyl [Fe(CO)5] on graphite basal-plane surfaces to be an extreme example of incomplete wetting in which only one solid layer of film coexists ...
Effects of hydrostatic pressure on the low-temperature photoluminescence spectrum of heavily doped CdS
(American Physical Society, 1985)
The photoluminescence spectrum of heavily doped CdS is studied under pressure at 300 and 6 K in a diamond anvil cell. The pressure-induced shift of the broad green luminescence peak at 300 K is found to depend on the ...
Photoluminescence studies of a GaAs-Ga1-xAlxAs superlattice at 8-300 K under hydrostatic pressure (0-70 kbar)
(American Physical Society, 1985)
The pressure dependence (0-70 kbar) of the photoluminescence spectra from a GaAs-Ga1-xAlxAs multiple-quantum-well (MQW) structure is reported at 8-300 K. The pressure coefficients of the EnhΓ and EnlΓ (n=1, 2) transitions ...
High-pressure studies of GaAs-Ga1-xAlxAs quantum wells of widths 26 to 150 Å
(American Physical Society, 1986)
Photoluminescence spectra of GaAs quantum wells of widths 26 to 150 Å are studied as a function of hydrostatic pressure (0-70 kbar) at 80 and 150 K. The pressure coefficients of both the heavy- and light-hole excitons are ...
High-pressure studies of GaAs-AlxGa1-xAs quantum wells at 300 and 80 K using photoreflectance spectroscopy
(American Physical Society, 1988)
A detailed photoreflectance study of a GaAs-Al0.3Ga0.7As multiple quantum well of well width 260 Å is carried out at 300 and 80 K. The pressure dependence of a large number of quantized states is observed. The sublinearity ...
Pressure studies of impurity levels in AlxGa1-xAs
(Institute of Physics, 1989)
The authors present a study of the deep and shallow donor levels under hydrostatic pressure. The shallow levels follow the conduction bands, while the deep levels are strongly sublinear with pressure. The temperature ...
Temperature dependence of the quantized states in a GaAs-Ga1-xAlxAs superlattice
(American Physical Society, 1988)
A detailed study of the photoreflectance spectra of a GaAs-Al0.3Ga0.7As superlattice as a function of temperature has revealed the temperature coefficients of the quantum- well transitions associated with the direct Γ ...
Multilayer structure of nitrogen adsorbed on graphite
(American Physical Society, 1989)
Elastic neutron diffraction has been used to study the structure and layering of nitrogen films adsorbed on the (002) surfaces of an exfoliated graphite substrate. The neutron-diffraction pattern of the fully compressed ...
Application of inelastic epithermal neutron scattering to the vibrational spectroscopy of adsorbed molecules: Butane physisorbed on graphite (0001) surfaces
(American Institute of Physics, 1984)
Inelastic epithermal neutron scattering (IENS) has been used to investigate the intramolecular vibrations of butane [CH3(CH2)2CH3] physisorbed on the (0001) surfaces of a graphite powder. The purpose of these studies was ...
On the representation of the electric charge distribution in ethane for calculations of the molecular quadrupole moment and intermolecular electrostatic energy
(American Institute of Physics, 1985)
It is shown that a simple atom‐site monopole model is inferior to one which includes higher‐order local multipoles to represent the intramolecular charge distribution of ethane. Unlike the latter model, the local monopole ...
Theoretical and experimental study of the vibrational excitations in ethane monolayers adsorbed on graphite (0001) surfaces
(American Institute of Physics, 1987)
The collective vibrational excitations of two different crystalline monolayer phases of ethane (C2H6) adsorbed on the graphite (0001) surface have been investigated theoretically and experimentally. The monolayer phases ...
Gradiometry and gravitomagnetic field detection
(National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Division, 1989)
Gravitomagnetism was apparently first introduced into physics about 120 years ago when major developments in electrodynamics and the strong similarity between Coulomb's law of electricity and Newton's law of gravity led ...
Orientational order in nitrogen monolayers adsorbed on graphite at low temperature
(American Physical Society, 1987)
Elastic neutron diffraction has been used to study the structure of N2 films adsorbed on the (0001) surfaces of an exfoliated graphite substrate at coverages CTHETA between 1.0 and 1.67 layers and at temperatures below 11 ...
Electronic Hamiltonian and antiferromagnetic interactions in La2CuO4
(American Physical Society, 1989)
A many-body Hamiltonian for La2CuO4 with ab initio parameters is solved numerically using embedded-cluster approximations. The results give an antiferromagnetic insulator with a 2-3 eV energy gap, consistent with spectroscopic ...
Neutron interferometry in a rotating frame of reference
(American Physical Society, 1988)
The physical basis for the description of phenomena by a rotating observer is investigated. A simple, yet tentative, extension of the hypothesis of locality is used to determine the interference phase shift induced by the ...
Layer-by-layer growth of solid argon films on graphite as studied by neutron diffraction
(American Physical Society, 1989)
The layer-by-layer growth of solid argon films on graphite at T=10 K is studied using elastic neutron diffraction. The growth is characterized by individual layers with commensurate in-plane lattice constants. As the ...